1. Chocobo's Dungeon + Pokemon Mystery Dungeon = Chocobo in Pokemon Mystery Dungeon: This seems kind of an obvious one, just cross Pokemon Mystery dungeon straight with Chocobo's dungeon. Pokemon monsters, Chocobo's Dungeon monsters, you can capture stuff, teach them special abilities, items, big boss battles. Their level they're marketed to seems to be the same as well. Overall, this just makes sense, but I don't see anyone realizing it.

2. New Super Mario Bros Wii + Megaman Powered up = Super Megaman Bros 3 Powered Up: Take the idea of Megaman powered up, then mix in some Mario Bros characters. Bowser stole Dr. Wily's robots, using them to kidnap the Princess and cause havoc in the Mushroom Kingdom, and its up to either Megaman or Mario to stop him. Megaman gains powers when he defeats bosses and Mario gains the ability to find new suits when he defeats bosses. Mario can then become Ninja Mario, Spinning Mario, Sharp Mario, or whatever is appropriate from that Megaman 3 boss. The Megaman 2 boss battles that come mid-way through the game are generic Koopa Kids but wearing various suits of Megaman 2 characters. Of course, being a Powered Up game, once you complete various robot masters, you unlock them to play as, and throughout the course of the game additional Mario Bros characters could become unlocked - Luigi, Wario, Princess Peach, Yoshi etc. Also, two player co-op for normal gameplay, and special four player co-op stages to play with friends with any characters the player has unlocked. This could be beyond epic, and I would totally buy a 3DS to play it. Sadly, I don't see it happening because the Megaman franchise has fallen on hard times and I don't see Capcom reaching out to do something unique.

3. The Matrix + Assassin's Creed = Matrix 1.0: Play as the first "One" in the fight against the Machines. You have to eliminate various programs within the system and gain information on a conspiracy unfolding within the Matrix. Battle against Agent Smith in his original incarnation and stop him from destroying humanity. I REALLY REALLY don't see this happening, but a new matrix IP would be pretty cool honestly, and Assassin's creed seems like it would mess well with it in some respects.

Barbie Wild Horse Adventure + Wolfenstein 3D

Sonic the Hedgehog + The Elderscrolls = Sonic the Dark Brotherhood... oh wait...

I'd play it.

On a related note:

• Care Bears and Left 4 Dead
  
• Strawberry Shortcake and Amnesia
  
• My Little Pony and Fallout (already been done in fan fiction)

http://www.escapistmagazine.com/articles/view/comics/critical-miss/8259-The-Crossover

A Super Smash Bros. game with characters from all companies.

K-On!! and Call of Duty

Super Smash Bros X MvC 3, lololol.

When I was younger (N64 was out), I had an idea for an online fighter. Some details:

- It would be like 32 people or more at once.
- Camera would be an over-the-shoulder 3rd person (movement is in 3D, not a 2D plane)
- The characters were the different elements (fire, water, earth, wind, and I had psychic in there as an unlockable "element", but looking at it now, that'd be silly and wouldn't work)
- Each element would be on a team
- They would battle it out in Battlefield sized arenas (destructable environments)
- Characters would be like Dragonball Z characters (movementwise, flying, projectiles, energy blasts, etc.)
- Each element would have special attacks specific to that element
- The elements have a "rock-paper-scissors" sort of relation (Water > Fire > Wind > Earth > Water) (or something)
- Your character would be persistent and level up. You would unlock new abilities and skill trees, armor and weapons
- And, of course, there'd be character customization.

Sooo, I guess a crossover between:

- Dragonball Z (fighting style)
- Multiplayer FPS
- Maybe a little MMO kinda with the skill trees

Barney's Hide and Seek and Manhunt.

Not exactly the same, but there's that Angry Bear game over whatever where you're a teddy bear and you murder people.

40K/WHF (depending on setting) + anything

Haha wow, that sounds [censored] amazing.

Madden+FIFA

Call of Duty+Harvest Moon

Playboy: The Mansion+The Bible Game

Warhammer 40K + Starcraft
Serious Sam + Painkiller
Poke'Mon + Big Game Hunter

I always thought a Assassins Creed and Batman crossover would be one of the most coolest things in the world. I could definetly find a way to have it all make sense to. Have The Templars and The League of Shadows have some sort of relation going on.

http://www.youtube.com/watch?v=lE1K9yNDNA8

Fallout: New Vegas and Final Fantasy 7.

Hell, FF7 is already in an apocalyptic setting, so we're half way there already!

Warhammer 40K + Pokemon. "Salamander, I choose you!" "Hey, he's evolving." "Just check the Liber Pokedex. Says he's evolving into the Forge-Father." "Iron Warrior, use dig."

Megaman X + Samus Aran. Samus teams up with X in order to take down a new breed of metroid reploids that are wreaking havoc across the galaxy.

Kid Icarus + Castlevania. Castle Dracula appears in Angel Land and all sorts of nasties begin pouring out of its gates. Pit must fight his way to the throne room to confront and defeat Dracula.

The Elder Scrolls + Soul Calibur.
Star Trek + Tom Clancy.

a highfantasy western crossover rpg, tes style, would be nice. i have been waiting for a game like that for a few years now.

p.s: i weely weely want magic and revolvers

Justice League vs Mortal Kombat
oh wait

Battlefield and Call of Duty.

Flame shield on!

Wouldn't it still be the same game?